Helm export YAML files locally (just use templating engine, do not send to Kubernetes)

37
votes

I want to export already templated Helm Charts as YAML files. I can not use Tiller on my Kubernetes Cluster at the moment, but still want to make use of Helm Charts. Basically, I want Helm to export the YAML that gets send to the Kubernetes API with values that have been templated by Helm. After that, I will upload the YAML files to my Kubernetes cluster.

I tried to run .\helm.exe install --debug --dry-run incubator\kafka but I get the error Error: Unauthorized.

Note that I run Helm on Windows (version helm-v2.9.1-windows-amd64).

3
kuberneteskubernetes-helm

3 Answers

50
votes

We need logs to check the Unauthorized issue.

But you can easily generate templates locally:

helm template mychart

Render chart templates locally and display the output.

This does not require Tiller. However, any values that would normally be looked up or retrieved in-cluster will be faked locally. Additionally, none of the server-side testing of chart validity (e.g. whether an API is supported) is done.

More info: https://docs.helm.sh/helm/#helm-template

17
votes

Amrit Bera's solution will only work with local helm chart, per the details of your question you want it to work with remote helm chart, that's a feature that will be added to Helm v3 (Work in Progress currently).

RehanSaeed posted the following workaround (https://github.com/helm/helm/issues/4527)

Basically:

mkdir yamls
helm fetch --untar --untardir . 'stable/redis' #makes a directory called redis 
helm template --output-dir './yamls' './redis' #redis dir (local helm chart), export to yamls dir

The good thing about this is you can mix this technique with weaveworks flux for git ops + this gives you another option for using Helm v2 without tiller, in addition to the Tiller Plugin (which lets you run tiller locally, but doesn't work smoothly).

11
votes

Straight from the helm install --help

To check the generated manifests of a release without installing the chart,
the '--debug' and '--dry-run' flags can be combined. This will still require a
round-trip to the Tiller server.